Pneumatic riveting-tool.



No. 703,753.4 rammed my l, |902.

.|. w. BmKENsTocK & n. w. Funk.

PNEUMATIC RIVETING TOUL.

(Application led Dec. 14, 1901.)

(No Mode.) 2 Sheets-Sheet L Il HHK-f Y TTOHNEYS l No. 703,758. Pafete'dJuly l, |902.

.1. w. BIRKENSTOCK a n.. w. FUNK.

PNEUMATIC RIVETING TOOL.

(Application led Dec. l14, 1901.)

. sectionsshowing the position of the piston UNI-TRD STATES ATRNT FFICE.

JOHN w. BIRKENSTOCK AND RICHARD w. FUNK, or Nnw YORK, N. Y., AssIeNORsTO THRl RIYIPIRRI PNEUMATIC TooI. COMPANY, oF NEW YORK, N. Y., ACORPORATION or NEw YORK.

PNEUMATIC RlVETlNG-TOOL.

SPECIFICATION forming part of Letters Patent No. 7 03,758, dated. July1, 1902.

Application iiled December 14, 1901l Serial No. 85,911. (No model.) l

T0 all whom t may concern.-

Beit known that we, JOHN` W. BIRKEN-v sToCK and RICHARD W, FUNK,citizens of the United States, residing in' New York, in the State ofNew York, have invented certain new and useful Improvements in PneumaticRiveting-Tools, of which the following is a speciiication.

This invention relates to an improved pneumatic tool intended for use asa tool for riveting, ramming, and similar purposes, in which tool theaction ofk a reciprocating hammer is used for accomplishing the rivetingor ramming action, the operation of the tool being controlled by asuitablev lever-operated valve by which compressed air is admitted to orshut Cif from the same; and the invention consists in thecombination,'with a casing provided with supply channels and ports, of ahandle atv one end of the same, a tool guided in the opposite end of thecasing, a piston-valve located at the interior of the casing, saidpiston-valve being hollow and provided with circumferential grooves andan opening in one of said grooves, a return-channel connecting the rear'end of the casing with the front end of the same, a sliding hammer inthe casing, a cushioning-spring located between the piston-valve andhandle, a channel connecting the interior of the casing with the ,spacebehind the valve, and shoulders at the rear endof the casing for'ar-fresting the spring and the piston-valve in their forward motion.

In the accompanying drawings, Figure lis a side elevation ofourjimproved pneumatic tool. Fig. 2 is a vertical longitudinal sectionof the sameron a larger scale, showing the piston-valve and piston'fininitial position. Figs. 3 and 4 are also vertical longitudinal andpiston-valve,respectively, after the blow has been given and preparatoryto returning to initial position. Figs. 5, 6, and 7 are verticaltransverse sections, respectively, on lines 5 5 and 6 6, Fig. 2, andline 7 7, Fig. 4; and Fig. 8 is a vertical longitudinal section of aportion of the tool, showing a modified construction.

Similar letters of reference indicate corresponding parts.

Referring to the drawings, A represents a cylindrical casing closed atits rear end by a head B, which is provided with a handle B', madebow-shaped and provided at its outer portion with a longitudinal recessin which are located, pivoted to the handle, two levers C C', the upperlever C being provided at its upper end with a `thumb-piece a and at itslower end with a knuckle a', that engages the upper end ofthe lowerlever C. In the lower part of the handle B/ is located an inclined borea3, in which is guided a reciprocating inlet-valve D of cylindricalshape, one end of the valve being engaged by the fulcrumed lever C, sothat when the upper lever C is pressed by the thumb of the user thevalve D is pushed forward in the bore a3, so as to place' an annularrecess o1 of the valve D in line with a nipple a5, to which the pipe etfor supplying air under pressure is screwed. When in this position, therecess 0.4 permits communication between the nipple and a supply-channelb, arranged in the handle. The channel ZJ communicates with alongitudinal channel b' in the cylindrical casing A. The socket or4 headB, by which the handle B is connected with the cylindrical casing orbarrel' A, is provided with an interior screwthread that screws over thethreaded end of the casing A and is locked in position by a winged keyd, that is located in a recess at the rear end of the casing A andengaged by the socket or head B of the handle, so as to .prevent anyunscrewing action between the handle and the Casin g by the'vibrationsto which the tool is subjected when in operation.

The socket or head'B is preferably made maketight joints with the shellA2. By making the casing of two parts, an interior stock and an exteriorshell, channels or air-ducts can be conveniently arranged by cuttinggrooves in the same, so as to dispense largely with the boring ofchannels, which is a more diflicult and expensive operation.

The channel b in the stock Al is'provided with two ports b2 b3, throughwhich pressure is supplied to the interior of the casing. A secondlongitudinal channel b4 is arranged in the casing diametrically oppositethe supplychannel b', said channel h4 being likewise provided with twoports d d2. The interior of the rear end of the casing is provided withtwo shoulders e2 e3, serving, respectively, as a support for a Washer cand as a means for arresting the piston-valve E, which is guided at theinterior of the casing and provided at its rear end c with a shoulder orrim c, that engages with the shoulder e3 when the valve is moved inforward direction. The pistonvalve E is made tubular and closed at therear end adjacent the washer e', but open at the opposite end, so as tocommunicate with the interior of the casing. Between the washer and thehandle is interposed a strong helical cushioning-spring f, which retainsthe washer normally against the shoulder e2. The piston-valve isprovided with two circumferential grooves e4 e5, corresponding,respect-ively, to the forward inlet-port b2 and with the rearmostoutlet-port d2. The groove or annular recess e4 communicates by anopening e6 with the cavity of the piston-valve and thence with theinterior of the casing. In front of the piston-valve E is located in thecasing a sliding hammer H, the diameter of the middle portion h of whichcorresponds to the inside diameter of the casing, while the ends aresomewhat reduced, the rear end corresponding in diameter to thecontracted rear portion f2 of the casing, in which the pistonvalve'E isguided. The shank of the tool is guided in the nose A3, forming theforward end of the casing and acted upon by a cylindrical block 77.2,which is acted upon by the forward end h3 of the hammer H.

In addition to the channels b b4 the casing is provided with anadditional channel b5 in lthe side Wall, said channel communicating withthe interior of the casing at a point opposite the reduced rear end hwhen in forward position and with the space b in the handle end of thestock,which is behind-z'. e. at the rear of the shouldered end of thevalve E. Two exhaust-ports d3 d4, arranged in the casing, communicate,respectively, with the groove e4 of the valve E when the latter is inforward position, as in Fig. 4, and with the groove e5 when in rearmostposition, as in Fig. 2, thereby permitting, respectively, escape of theair behind the hammer on the return and escape of the air in front ofthe hammer on the forward stroke.

When the outlet-valve D is opened by pressing the handle C in theposition shown in Fig. 2, compressed air is conducted through theChannels I) I?, 31nd the 0IOOVS 6481116. 0 @Ding G6 v to the interior ofthe valve E and thence to the interior of the casin g. By the compressedair the piston or hammer H is driven forward, f

space bs. The rear end c of the valve E has va v slightly-larger area,owing to its shoulder e, than the opposite end of the valve or, in otherwords, than the surface opposed thereto.

Both surfaces being under equal pressure per g unit of area, but ofunequal area, .the air forces the valve E forward until theL rim e abutsagainst shoulder es, as shown in Fig. 4. This action takes placeimmediately after the blow is struck or at such time about the' time ofthe blow that the force of the same is not affected, and immediatelythereafter by passage of the air under pressure through the channel b',port b3, groove e5, port d', and the return-channel b4 into the spacebetween the block h2 and the body h ot'v the hammer the latter isimmediately returned to its position at the rear end of the casing,where it abuts against the valve E, and the latter through washer eagainst the cushioning-spring f. When the reduced rear end h' of thehammer enters the reduced portion f2 of the casing, escape of airbetween the same and the body 72, of the piston is thereby cut off andthe air inclosed in the annular space f3 acts,.in addition to the springf, to cushion'the hammer on its rearward stroke. As soon as the valve Eis shifted into position shown in Fig. 4 the groove e4 is placed in linewith the exhaustport d3, so that the air under pressure atthe interiorof the casing behind the hammer is allowed to escape as the hammerreturns. The springfafter compression immediately expands to itsoriginal condition, thereby placing the valve E in position foradmitting air for another forward stroke of the hammer, Fig. 2. Duringthe forward movement of the hammer the air in front of the same passesthrough channel b4, port d2, groove e5, and port d4 to the outsideatmosphere. Backand-forth movement of the block h2 is limited at oneside by the smaller outer end of the stock A and at the other by ashoulder d of the nose or end piece A3.

For stopping the tool the pressure of the `thumb of the operator on thethumb-piece a,

is released, and the inlet-valve D is returned into closing position andretained in closed position by pressure of air against the outer end ofthe valve, the compressed air being conducted by a small bore or duct gfrom the nipple a5 to the outer end ofthe bore CL3. The levers C C' areby this operation moved into the positions shown in dotted lines in Fig.2. Y

IOO

IIO

The tool shown in Figsl to 7 ismainly intended as a tool for rivetingand similar work. Fig. 8 shows a slight modification rendering the toolmore suitable for use as a rammer. In this view A4 is the stock; A5, theshell; CV, a bore corresponding to h5; d8, the returnbore, and H theyhammer. h4 is the block, limited in movement by the outer end of thestock and a shoulder h of the nose h2. The shank t of the rammer TWithin the nose and forward of the block h4 isv enlarged. Forwardmovement of the tool is limited by abutment of the enlargement h againsta shoulder h7 of the nose H2. A duct h3 of smaller cross area than theduct (ZS communicates with the same and opens into the interior of thenose H2 forward of the enlargement, thereby serving to return the toolto striking position when the hammer is returned. The construction ofthe tool in the parts not shown is identical with the correspondingparts of the tool iirst described.

Having thus described our invention, we claim as new and desire tosecure by Letters Patents l. The combination,with a casing provided withsupply channels and ports, of a handle at one end of the same, a toolguided in the opposite end of the casing, a piston-valve located at theinterior of the casing, said pis- 4ton-valve being hollowr and providedwith circumferential grooves and an opening in one of said grooves, a.return-channel connecting the rear end of the casing with the front endof the same, a sliding hammer in the casing, a cushioning-spring locatedbetween the piston-valve and handle, a channel connecting the interiorof the casing with the space behind the valve, and shoulders at the rearend of the casing for arresting the spring andthe piston-valve in theirforward motion, substantially as set forth.

2. The combination, with a casing, of a bow-shaped handle attached tothe rear end of the same, an inlet-valve in the handle, a supply-channelin the handle communicating with the supply-tube, a supply-channel inthe rear portion of the easing, provided with ports, a hollowpiston-valve in the rear portion of the casing provided with twocircumferential grooves and an opening in one of said grooves, a slidinghammer in the casing,`

a sliding' block closing the front end of the casing, a channel in thecasing for supplying compressed air for the return of the hammer, achannel connecting the interior of thecasing with the space between thepiston-Valve and the handle, and exhaust-ports for permitting escape ofair from the interior of the casing between the slide-block and hammer,

Vand between the hammer and piston-valve,re

spectively on the forward and return strokes of the hammer,substantially as set forth.

3. The combinatiomwith a casing, of a handle attached to the rear" endof the same, an' inlet-valve in the handle, a supply-channel in thehandle, a supply-channel inthe rear ssv ders at the rear portion of thecasing, a spring between the rear shoulder and the handle, a

vrim on thepiston-valve adapted to abut against the other shoulder, thearea of the rear end of said valve being slightly larger' than that ofits front end, a sliding hammer in the casing, a channel connecting theinterior of the casing with the space behind the piston-valve, andexhaust-ports communicating with the interior of the'casing,substantially as set forth.

In testimony that we claim the foregoing as our invention We have signedour namesin presence of two subscribing witnesses.

JOHN W. BIRKENSTOCK.- RICHARD W. FUNK'.

Witnesses:

PAUL GoEPEL, JOSEPH I-l. NILEs.

